Assistant Kane County State's Atty. Greg Sams, who will prosecute the case, said he had been in contact with Long's family and that they supported the murder charge against Cook.

"Our hearts go out to the Long family," said Batavia Police Gary Schira, who noted Long walked his dog daily around 6:30 a.m.

Barsanti said his office was pressing the murder charge based on provisions in state law that allow it in cases where a victim is killed during the commission of a forcible felony.

In the Cook case, those alleged forcible felonies include aggravated driving under the influence and burglary, which was charged because Cook did not have permission to drive the 2003 Acura involved in the crash, Barsanti said. He also was driving on a revoked license.

The charging documents name the vehicle's owner, and authorities said Monday that Cook and the woman had a "relationship," though they declined to offer more specifics. At Cook's initial court appearance, it was disclosed that Cook told police he was rushing to meet his girlfriend, who was late for work.

Should Cook, who served prison time in 2008 on an aggravated DUI conviction, be found guilty of murder, he would face a minimum sentence of 20 years and a maximum of 60 years in prison. Cook was initially charged with aggravated DUI, which carries a maximum sentence of 14 years.